Binocular loupes have conventionally been used widely in each field such as the medical field, precision work, jewel processing and the like, as means for magnifying a local visual subject at hand to visually identify. In these fields, high precision is required in the work and operation, and particularly, in the medical field, since the field involves human lives, vision correction and astigmatism correction of the binocular loupe is required to precisely adapt to the vision of a worker.
Further, in addition to excellent resolution, wide viewing diameter, deep focal length and the like, since bright clear image quality is required, and ease in handling and ease in maintenance is demanded, waterproof processing enabling water washing, and anti-corrosion processing is needed. Further, it is necessary to configure adjustments of magnification of a main-glass loupe to be adjustable according to the use.
As an example of such a binocular loupe, Patent Document 1 discloses a structure of a binocular loupe enabling adjustments of a pupil distance i.e. attachment positions in the horizontal direction of eyepiece barrels.
Patent Document 1: Japanese Patent Publication No. 2005-257802